HOMEMADE PORTE Lt;jriERE. 



179 



ends and bottom by a thick rubber tube and clamped 

 together, is filled with a saturated solution of alum 

 and set in front of the condenser. 



A microscope is set on the transverse board so that 

 the front of the object glass shall be at or near the 

 focus of the condenser. An object is placed upon the 

 stage, the mirror of the microscope is turned out of 



HOMEMADE PORTE LUMIERE. 



(Arranged for projecting mlero.scopiu objects.) 



the way, the tube is placed horizontally, and the 

 image is projected upon a wall or screen and focused 

 by the microscope adjustment. The room of course 

 must be darkened. Screens made of carpet paper or 

 black calico are very effective ; but if regular opaque 

 shades mounted on rollers can be procured, of course 

 they are to be preferred. With this instrument, a 

 microscopic object is seen by a whole class at once in 

 its natural colors. Moving objects, such as proto- 



